As has been well known, hydrogel soft contact lenses of permanent-wear or periodic replacement type need to be stored in a condition of being soaked in a preserving solution such as physiological saline containing a disinfecting component etc. and protected from drying out or contamination during a period from the removal of the lens from the wearer's eye to the next application thereof. When more certain disinfecting effect is expected, the contact lenses are soaked in hydrogen peroxide solution for more than several hours for disinfection.
By the way, as a structural body that can easily contain and store a liquid agent such as the preserving solution mentioned above or hydrogen peroxide solution as well as contact lenses, a contact lens case has conventionally been used widely. For example, as described in Japanese Unexamined Patent Publication No. JP-A-2002-006274 (Patent Document 1), the structure of the contact lens case comprises a container main body provided with a housing recess for storing preserving solution and contact lenses and a lid installed at the upper opening of the housing recess to cover the upper opening. Also, as a contact lens case capable of providing disinfection using hydrogen peroxide solution, Japanese Domestic Publication of International Patent Application No. JP-A-2002-526203 (Patent Document 2) proposes a case having a structure where a platinum layer is applied to the bottom surface and inner peripheral surface of a shallow housing recess. That is, although hydrogen peroxide solution is decomposed into nontoxic water and oxygen, any undecomposed residue would serve as stimulus against the eyes, and therefore, hydrogen peroxide should be completely neutralized by dissolution before the completion of the disinfection treatment of the contact lenses by means of accelerating and adjusting the dissolution reaction using a catalyst such as platinum.
However, various problems have been pointed out in terms of hygiene, safety and operability of the conventionally structured contact lens case described above. For example, in storing contact lenses that have been worn all day, there is a case where a liquid agent such as a preserving solution or hydrogen peroxide solution is filled in the housing recess of the contact lens case, and then the contact lenses are removed by being picked with the user's fingers from the user's eyes to be stored in the housing recess. In this case, there is a good possibility that the user's fingers get in touch with the preserving solution, and if the liquid agent is indeed a preserving solution, there is a concern about the preserving solution being contaminated by the contact with the user's fingers. If the liquid agent is hydrogen peroxide solution, there is a risk that the user's fingers would touch the solution before neutralizing reactions, which is an irritant substance, when one of the contact lenses is stored in the housing recess, and when the other contact lens is removed from the eye with the fingers, hydrogen peroxide solution would get into the eye.
Also, in case of reusing contact lenses stored in a contact lens case, the user has to insert his/her fingers into the housing recess filled with a liquid agent to pick up each contact lens. Therefore, it is inevitable to spill the liquid agent over the housing recess where the fingers are inserted, thus causing a problem of being unable to wear on the contact lenses except in the place where spilling of the liquid agent causes no problem. Also, when the contact lenses are picked up from the liquid agent, there could be a risk that the contact lenses may float within the liquid agent and turn upside down, thereby preventing them from being easily picked up from the housing recess.